Scientists are claiming that carbon nanotubes can do just about everything -- and now we can add tire-tread monitoring to that list.
Electrical engineers at Duke University in North Carolina have come up with a printed sensor that is capable of monitoring tire tread in real time. When the tire gets low on tread, the inexpensive sensor, which is embedded inside the tread, can warn the driver that it's time to head to the tire shop.
The sensors, created in collaboration with Fetch Automotive Design Group, rely on metallic carbon nanotubes, a tightly arranged mass of carbon atoms measuring just one nanometer in diameter. The sensor works by creating an electrical field between two electrodes with an oscillating voltage. The tread interferes with the field in a very specific way, which allows the sensor to track tread depth on the scale of millimeters with near-perfect accuracy.
This sensor could be made from different materials using different methods, but the most successful results came from printing metallic carbon-nanotube electrodes on a flexible film. The nanotubes provide enough durability to live inside a tire, and it's estimated that economies of scale can bring the sensor cost down to less than $0.01 per unit.
Two patents related to this technology are already pending, and the researchers are currently working to establish connections in the auto industry in order to bring this technology to mass-market vehicles. A paper on this technology was published June 9 in the IEEE Sensors Journal.
These researchers are on to something. Being able to monitor tire pressure in real time has been so important to driver safety that it's become a mandatory feature in vehicles. Tire pressure sensors are far from inexpensive, so if it only costs a penny or two to also add tread-depth monitoring, it's a low-cost way to push safety even further.